Electromagnetic rotary armature relay



g 1967 E. w. BAYER ETAL 3,336,550

ELECTROMAGNETIC ROTARY ARMATURE RELAY Filed Sept. 16, 1964 2 Sheets-Sheet 1 e5 2 5 anllill W 63i64 I 35 INVENTORS ERIC w. BAYER 53 I? WERNER MULLER ATTORNEY ELECTROMAGNETIC ROTARY ARMATURE RELAY Filed Sept. 16, 1964 2 Sheets-Sheet 2 INVENTORS, ERIC W. BAYER WERNER MULLER ATTORNEY United States Patent 3,336,550 ELECTROMAGNETKC ROTARY ARMATUIRE RELAY 3 Claims. (Cl. 335272) This invention relates to the art of relays and, more particularly, to an electromagnetic rotary armature relay having improved features of design and construction. The invention pertains, in one of its more specific aspects, to an electromagnetic rotary armature switching relay that is adapted to be readily made in small and miniature sizes and that is capable of rendering efiicient and dependable service under various conditions of use.

Among the desired objectives successfully.attained by the relay of this invention are miniaturization of multipole switching relays and improved performance thereof as regards load life, eflicency and reliability under severe conditions of use in various environments, such as aircrafts, missiles and the like, which are frequently subjected to high inertia forces due to shock, vibration and continued acceleration or deceleration and in which space for operating equipment is limited.

Another design objective attained by our present relay is economical manufacturing cost without sacrifice in quality or performance. This objective is realized by reducing the number of parts to an essential minimum, thereby correspondingly reducing the number of assembly operations with attendant economies in labor costs.

Incorporated in the relay of this invention are a number of novel and useful features which contribute to its utility and reliable performance over extended time periods and under severe use conditions.

One of the important features of the invention resides in the provision of a highly eflicient motor structure which is characterized by a minimum number of magnetic parts, namely, a shell unit, a core and a rotary armature unit which are so designed and arranged as to substantially surround or envelop the magnetizing coil. The motor structure is also characterized by the number and placement of working and non-working air gaps. In this connection, a single working armature gap is provided in the most etficient location, namely inside the magnetizing coil, thus providing high open air gap pull. A constant non-Working air gap between the outside diameter of the armature unit and the inside diameter of the shell unit lowers the holding force of the motor. This is very desirable because it eliminates the need for heavy plating or the use of shims in the pole face area to meet drop-out voltage requirements.

A second important feature of this invention resides in the utilization of improved connector means which serves the dual functions of physically coupling the armature unit to the core and permitting rotational orpivotal movement of the armature unit relative to the pole pieces. The connector means includes a pair of stainless steel balls and associated parts which are so configured and arranged as to attain compactness, accuracy, low friction, long life and minimum play at low cost.

Another important feature of the invention resides in an improved balanced rotary armature which successfully withstands inertia forces. As a consequence, only a light duty holding spring is needed and a relatively small electrical force is required to actuate the armature against the action of the spring.

The primary object of this invention is to provide an electromagnetic relay having improved and simplified fea tures of design and construction.

3,336,550 Patented Aug. 15, 1967 The invention has for another object the provision of an electromagnetic rotary armature relay that is capable of being made in small and miniature sizes and that is adapted to effectively withstand shock and vibration forces and conditions of acceleration or deceleration in the course of normal use.

A still further object of the invention is to provide an electromagnetic relay of the character indicated that is small, compact and light Weight in design; that is sturdy and durable in construction; that is economical in manufacturing costs and that is capable of performing its intended functions in a satisfactory and reliable manner.

The relay of this invention may be advantageously employed with various types of switch arrangements including, but not limited to, single pole, double throw switches and multi-pole, double throw switches. The following detailed description and the accompanying drawings describe and illustrate, by way of example, a relay according to the invention for operating a four pole, double throw switch arrangement.

In the drawings, wherein like reference characters denote corresponding parts throughout the several views:

FIG. 1 is a central vertical cross sectional view through a complete relay constructed in accordance with this invention;

FIG. 2 is a top plan view of the relay shown in FIG. 1 with the cover unit and the header unit omitted;

FIG. 3 is a view taken along line 3-3 of FIG. 2;

FIG. 4 is a bottom plan view of FIG. 3;

FIG. 5 is a top plan view of the header unit of the relay, certain parts which are duplicates of illustrated parts being omitted;

FIG. 6 is a side elevation view of the header unit shown in FIG. 5; and

FIG. 7 is an exploded view of the relay on a reduced scale, certain parts which are duplicates of illustrated parts being omitted.

Referring initially to FIGS. 1 and 7, the complete relay illustrated therein is made up of five principal parts, namely an electromagnet unit E, a rotary armature unit A, a shell unit S for housing the electromagnet and armature units, a header unit H and a cover unit C, and a number of secondary units or parts, all of which will now be described.

Electromagnet unit E comprises a bobbin 10 which defines an axial through opening 11. The bobbin includes an upper flange 12 and a lower flange 13 which is parallel to and spaced from the upper flange. The lower flange is provided with a pair of integral, depending and diametrically arranged tubular extensions 14. A magnetizing coil 15 is wound on the bobbin and terminates in a pair of electric leads 16 and 17, each of which extends through a corresponding tubular extension 14. The coil is provided with an insulating outer wrapper 18.

The electromagnet unit also comprises a unitary core 20 which is preferably made of sintered magnetic iron. The core consists of a circular plate 21, having a central through opening 22, and a pair of spaced, parallel, depending pole pieces 23 and 24 which are normal to plate 21.

A sintered stainless steel spacer 25 is positioned be tween and in intimate contact with the facing arcuate surfaces of pole pieces 23 and 24 and is firmly secured thereto by brazing. Spacer 25 is in the form of a rectilinear rod having semi-spherical indentations or recesses at the upper and lower ends of its longitudinal axis, as indicated at 26 and 27, respectively.

Shell unit S houses electromagnet unit E and serves as a support therefor and for associated parts. The shell unit comprises a right circular cylindrical steel tube 28 which is open at its ends. Integral with tube 28 is a plu- J rality of circumferentially spaced legs which terminate in corresponding feet 31. Tube 28 is formed at its upper end with an internal annular recess 32 and at its lower end with an internal annular flange 33.

At the time of assembly, the parts of electromagnet unit E are arranged in shell unit S, as shown in FIG. 3, with lower flange 13 of the bobbin bearing against annular flange 33 of tube 28 and with core plate 21 bearing against upper flange 12 of the bobbin and registering with tube recess 32. The upper extremity of tube 28 is then peened over the upper marginal surface of the core plate whereby the indicated parts are securely maintained in the illustrated relative position.

Reference is next had to armature unit A which is best shown in FIGS. 1, 3 and 7. The armature unit, as in the case of core 20, is preferably made of sintered magnetic iron and consists of a circular plate 35 and a pair of upstanding arms or members 36 and 37 which are normal to plate 35 and are disposed to opposite sides of its axis. Plate 35 is formed with a central through opening 33 and a pair of diametrically arranged peripheral recesses 40, one of which is shown in FIG. 7. A tap 41 is provided in the upper end of each armature member. As is indicated in FIGS. 2 and 7, armature members 36 and 37 are located in bobbin opening 11 and are disposed between corresponding planar faces of pole pieces 23 and 24.

The armature unit is mounted for rotary movement about the longitudinal axis of spacer rod 25 through the medium of connector means including a bridge device 42 which extends across the space between the pole pieces and is secured to the free ends of armature members 36 and 37. The bridge device is in the form of a plate having a pair of openings 43 and provided with an upwardly projecting extension 44. A stainless steel ball 45 is welded to the under surface of device 42 midway between openings 43. This ball is seated in upper indentation 26 of spacer rod 25 and serves as a low friction rotary or pivotal connection between the indicated parts. A. stub shaft 46 is welded to the top of device 42 directly above the steel ball. The bridge device is secured to the armature members by means of screws 47 which extend through openings 43 and engage corresponding taps 41 in the armature members. Mounted on the stub shaft is a helical spring 48. One end of this spring bears against extension 44 and the other end bears against a portion of core 20 which defines opening 22. The parts are so constructed and arranged that spring 48 normally and yieldingly biases the armature in a clockwise direction of rotation relative to the pole pieces, as viewed in FIG. 2, to the extent allowed by engagement of extension 44 with another portion of the core that defines opening 22, as shown in FIG. 2.

The illustrated relay of this invention includes a switch actuator 50 which also constitutes part of the earlier referred-to connector means. The switch actuator comprises a plate 51 which bears against and is secured by welding to the lower surface of armature plate 35. Plate 51 has four angularly spaced L-shaped fingers 52, each of which carries an insulating element, such as a glass bead 53, at its free end. Plate 51 is provided with a pair of diametrically arranged peripheral notches 54 which are aligned with corresponding notches in armature plate 35 to accommodate corresponding bobbin extensions 14. A stainless steel ball '55 is spot welded at the center of the top of the plate 51 and is seated in lower indentation 27 of rod 25 to form a low friction connection therewith. It will be noted from an examination of FIGS. 1, 2 and 3 that the illustrated arrangement of spacer rod 25, steel balls and 55 and associated parts permits limited rotation or pivotal movement of the armature rela tive to the core in either direction.

Header unit H will now be described, having reference to FIGS. 5, 6 and 7. This unit comprises a base plate 57 having a plurality of peripheral notches 58 for receiving corresponding feet 31 of shell unit S. The shell feet are firmly anchored to the base plate by spot welding, there- 4 by attaining a sturdy unitary arrangement of shell unit and header unit.

The base plate carries a plurality of fixed terminals, namely a pair of terminals 60 and 61 and four sets of terminals 62, 63 and 64, the terminals of each such set being arranged triangularly. All terminals extend through the base plate and are anchored thereto by corresponding masses of an appropriate, rigid insulating material, such as glass, as indicated at 65 in FIGS. 5 and 6. Terminals 60 and 61 are respectively connected to coil leads 16 and 17.

Affixed to each terminal 62 by brazing is a generally I- shaped movable contact 66. A generally V-shaped stationary contact 67 is secured by brazing to each terminal 63 and a like stationary contact 68 is secured in the same manner to each terminal 64. As is best shown in FIG. 5, the free end portion of the therein illustrated movable contact 66 is positioned between stationary contacts 67 and 68 and is so configured and arranged as to normally and yieldingly engage stationary contact 67. While the drawings depict only one set of terminals 62, 63 and 64 equipped with contacts 66, 67 and 68, respectively, it will be appreciated that each set of such terminals is usually equipped with corresponding contacts.

Each movable contact 66 of a complete relay extends across the path of travel of a corresponding actuator bead 53. The arrangement of movable contacts and actuator beads is such that, upon predetermined pivotal movement of armature unit A in one direction, the illustrated movable contact 66 is engaged and flexed by an acuator bead in a counter clockwise direction, as viewed in FIG. 5, to thereby break contact with stationary contact 67 and make contact with stationary contact 68.

Cover unit C is cooperatively arranged with base plate 57 to encase the parts of the relay which are located above the base plate. The cover unit comprises a tubular side wall 70 and a circular top wall 71. This unit is open at its lower end for the reception of various parts of the relay and forms a snug fit with the base plate. The cover unit is hermetically sealed to the base plate at the time of assembly. The cover unit is provided with an external ring 72 proximate its open end. Ring 72 has a pair of diametrically opposed lateral flanges 73, each having an opening 74 for the reception of a screw or other attaching means in mounting the relay to a panel board or other selected location.

The operation of the herein described form of the invention will now be briefly described, it being assumed that the illustrated relay is assembled and that the parts are in the relative position shown in FIGS. 1 and 2. It is also assumed that magnetizing coil 15 is deenergized. Under these circumstances, armature unit A is biased in a clockwise direction of rotation about the pivotal axis formed by steel balls 45 and 55, as viewed in FIG. 2, by the action of spring 48 and is maintained in position by engagement of device extension 44 with a portion of core plate 21 which defines opening 22. With the parts in the indicated relative position, actuator beads 53 are out of engagement with corresponding movable contacts 66.

When header terminals 60 and 61 are connected to a suitable source of electric energy and the magnetizing coil is energized, pole pieces 23 and 24 exert sufficient attracting force on armature members 36 and 37 to impart reverse pivotal movement to the armature 'against the action of spring 48. Thus, the armature is pivoted in a counter-clockwise direction, as viewed in FIG. 2, toward and to the extent allowed by the pole pieces. This movement of the armature causes each actuator bead 53 to engage and flex a corresponding movable contact 66, thereby breaking contact between each movable contact and a corresponding stationary contact 67 and making contact between each movable contact and a corresponding stationary contact 68. Upon deenergization of the magnetizing coil, the parts automatically return to their original position by the action of spring 48.

From the foregoing, it is believed that the objects, construction and operation of our present invention will be readily comprehended by persons skilled in the art Without further description. Although the invention has been herein shown and described in a simple and practicable form, it is recognized that certain parts thereof are representative of other parts which may be used in substantially the same manner to accomplish substantially the same results. Therefore, it is to be understood that the invention is not to be limited to the exact details described herein, but is to be accorded the full scope and protection of the appended claims.

We claim:

1. In an electromagnetic relay, a magnetizing coil defining an axial through opening, a core associated with the coil and comprising a pair of spaced pole pieces in the coil opening, an armature comprising a plate which is adjacent an end of the coil and a pair of spaced members in the coil opening, one of the members being positioned be tween a side of one of the pole pieces and a side of the other pole piece, the other of said members being positioned between the opposite side of said one pole piece and the opposite side of said other pole piece, support means carried by the core and positioned in the coil opening, connector means connecting the armature to the support means and permitting rotary'movement of the armature relative to the support means, said connector means comprising a device secured to the plate and an element intermediate the device and the support means permitting relative movement thereof, and biasing means normally urging the armature in one direction of the rotation relative to the support means and maintaining the members in a predetermined position away from the pole pieces, the armature being adapted, upon energization of the coil, to be moved in a reverse direction against the action of the biasing means by magnetic attraction between the pole pieces and the members.

2. In an electromagnetic relay, a magnetizing coil defining an axial through opening, a core associated with the coil and comprising a first plate adjacent one end of the coil and a pair of spaced pole pieces in the coil opening and substantially normal to the first plate, an armature comprising a second plate substantially parallel to the first plate and positioned adjacent the other end of the coil and a pair of spaced members in the coil opening and substantially normal to the second plate, one of the members being positioned between a side of one of the pole pieces and a side of the other pole piece, the other of said memers being positioned between the opposite side of said one pole piece and the opposite side of said other pole piece, support means carried by the core and positioned in the coil opening, said support means comprising a rectilinear part secured to the pole pieces and positioned wholly within the coil opening, connector means connecting the armature to the support means and permitting rotary movement of the armature relative to the support means, said connector means compn'sing a first device secured to the members and extending across the space between the pole pieces, a first element intermediate the first device and one end of said part permitting relative pivotal movement thereof, a second device secured to the second plate, and a second element intermediate the second device and the other end of said part permitting relative pivotal movement thereof, and biasing means normally urging the armature in one direction of rotation relative to the support means and maintaining the members in a predetermined position away from the pole pieces, the armature being adapted, upon energization of the coil, to be moved in a reverse direction against the action of the biasing means by magnetic attraction between the pole pieces and the members.

3. An electromagnetic relay according to claim 2 wherein the first and second elements are spherical.

References Cited UNITED STATES PATENTS 2,298,227 7/ 1942 Walker 317-197 2,364,656 12/1944 Price 317-97 2,916,584 12/ 1959 Molyneux.

3,157,803 11/1964 Grayson 317-197 BERNARD A. GILHEANY, Primary Examiner. G. HARRIS, JR., Assistant Examiner. 

1. IN AN ELECTROMAGNETIC RELAY, A MAGNETIZING COIL DEFINING AN AXIAL THROUGH OPENING, A CORE ASSOCIATED WITH THE COIL AND COMPRISING A PAIR OF SPACED POLE PIECES IN THE COIL OPENING, AN ARMATURE COMPRISING A PLATE WHICH IS ADJACENT AN END OF THE COIL AND A PAIR OF SPACED MEMBERS IN THE COIL OPENING, ONE OF THE MEMBERS BEING POSITIONED BETWEEN A SIDE OF ONE OF THE POLE PIECES AND A SIDE OF THE OTHER POLE PIECE, THE OTHER OF SAID MEMBERS BEING POSITIONED BETWEEN THE OPPOSITE SIDE OF SAID ONE POLE PIECE AND THE OPPOSITE SIDE OF SAID OTHER POLE PIECE, SUPPORT MEANS CARRIED BY THE CORE AND POSITIONED IN THE COIL OPENING CONNECTOR MEANS CONNECTING THE ARMATURE TO THE SUPPORT MEANS AND PERMITTING ROTARY MOVEMENT OF THE ARMATURE RELATIVE TO THE SUPPORT MEANS, SAID CONNECTOR MEANS COMPRISING A DEVICE SECURED TO THE PLATE AND AN ELEMENT INTERMEDIATE THE DEVICE AND THE SUPPORT MEANS PERMITTING RELATIVE MOVEMENT THEREOF, AND BIASING MEANS NORMALLY URGING THE ARMATURE IN ONE DIRECTION OF THE ROTATION RELATIVE TO THE SUPPORT MEANS AND MAINTAINING THE MEMBERS IN A PREDETERMINED POSITION AWAY FROM THE POLE PIECES, THE ARMATURE BEING ADAPTED, UPON ENERGIZATION OF THE COIL, TO BE MOVED IN A REVERSE DIRECTION AGAINST THE ACTION OF THE BIASING MEANS BY MAGNETIC ATTRACTION BETWEEN THE POLE PIECES AND THE MEMBERS. 